Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70876809cdc5cbb56e155eb8da74857d8548f8e630411f41ce1d43b4cdb26e51' 
  AND token = 'mDYhA+AlDY1mxFL87A2SUc57Zdr6shwkzLx70qS0+a0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}