SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8412038f6bd097789bd73c634ac7195260e4360243298d1650d8eee1be4d8203' 
  AND token = 'vH+ZuZB+6ZvqUJfxDvRLoSgGLzhS77HL1k7JXyqPwIA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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