Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd40691a8f01ee60444686e9df2a574cabb9b4ae1c06455a7937acedeaca69e38' 
  AND token = '2UJ86vfSN3xxIfxytdNoyiv8+uWSI/pA+sw+HUWYRN0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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