SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f184c1735106fafbab147055fbac6a029c1882da288a4f8d5761670aea9a6231' 
  AND token = 'u3wiUt8km7LQRx06GazW903ToKdvE3Ouj9WdJwmY+Lw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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