SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09610b559bd29db2b328fb0bcdc41a576d738663437ae3e23d156bf108542ea2' 
  AND token = 'PpwYZYMVXhB6i27yuvRoFUpdJW6eO3ftUKDEqezQ//g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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