SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11474251cc2e99d0aed3cc994895b2f7f78576dc731e323593c76ad3ac0fb314' 
  AND token = 'tIrtx+4aVPK5wvmp9VJq7xBjtjV1TAUKmq4eRwF7b2g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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