Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de390f55f89b7722991c81d13c1606999a55baa36658e43d9f316171bb32cfbc' 
  AND token = 'EZVrxrST64R6xqVQO3gjrU9hq2azNM15VS8ho0PWhmA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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