SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c764b6be2365955160de9988a8a8ee6049cd2b22c6d8d826a57da3fc4bd20281' 
  AND token = 'Vq9z0XwuLDGtIvC/6zXnKaE3CbICgVMBfHwaxyeXSIo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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