SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5216352f6cf0ff8bbb992269d12c677823afcb9e3a04904d6c450c3ff5ded83d' 
  AND token = 'h5Ak7Hc8bPs+5TAWCx7d928JNyB0EaYvHonkT1ZDxjE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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