SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '657bce5086247fd1719509b132497a1fbb13b3c5800d0ddd8a29ee946b75d55d' 
  AND token = '6TFfZ5paH35J2VyLehHCwXQ5GObxoqb/q6KdBycE5M8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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