SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ecfc17ac045bd8c2553aa1cecbf27131f1b9f4d92b9ffbbe2128028fafe82810' 
  AND token = 'aVYbQWRnVZSyBj0d37YeWIgRObEigjI83eIC7PcmLHI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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