SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '690571c384fb755596272fa227013f1bf7d9cf1c11058eff8411906cd25528b1' 
  AND token = 'TAZyHt94mIRoIxWgf3rL+ABQ5FkcT0KFJMmgNdkapGQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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