SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'acc9d59d04a88be3d111866a330c6edfd2663eeb24090196f6080019b5e6c9e0' 
  AND token = 'QZ6OiwLp7Bi4706qat46TuWffbOKvF7auCGJb/bMKZ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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