SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '90004a64e4b9fb67f42c459ffa05e424f8c6dfc16f267287773820de31e48a6d' 
  AND token = 'bX1hrCB1QvwEz1WyqrU8UsFOU2OFLFJj9tZmhdu7/5k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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