SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ba9d80aeae2e39df4321bd5598139298609e8383bae5422299fa1d8426e5f67' 
  AND token = 'LrMmspD2S1AZhZrVmQmaKzog76jYLSjZRlHf7rlP6Bs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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