SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e026fb9327d29619a9c504c473cc7c995726793fb8745cbad852948bc5f9a40d' 
  AND token = 'dF3lxTUuUrvy1mmShHPHkNFbsL9tdShFD3hI0QNTOQI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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