SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed0fd0767882364c54538496d2919e811ef26c39c69ca27d9c6581589eec8567' 
  AND token = 'kqtQELlBQYgWXQ3heDHmaTjUCBYK3Pv/DRPfsz1JeBU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}