SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd11600c055545b265d66ce8387fe8fc547b27b92af4836c16cefb0127b810477' 
  AND token = 'Zu6uMw3Vh2zfV/X3uLLvCpTXTlOPDOAwbE1d52GHUMY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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