SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d333afcf6563818613eee1561a0aa547ccdfd3535564e6fab7f5a8bc22a2651' 
  AND token = 'lRYOSnUQIprBGX9+U3sKSxMk/LJTXgF49q+I+uXSJRA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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