SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f35b5666277528be9c70f422c785ccc55ab07bc423b852885d76a46b0a6f135' 
  AND token = 'gGyI2C44sm1Y1Q7PXZEuQTWQT2R568rovfCXqVaTd64=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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