SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7fd1b35f884f43c3c13be4a00c4a8ca831159a59a8f16d2f74c19b7d6e53afb0' 
  AND token = 'Pp+RJrIqrbFOdUgflnEOvTLDRrp0sk9K2M+9+lWuEcU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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