SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5cbe518d8018720da2385ac1f17232a0a99db9ac2bf7eb1ebf492c354f2cb169' 
  AND token = 'DN+7h6QunIrG/RsXEKf+Pq00V7Iudc3m/xGemepIPt8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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