SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '96c16053db483b76507c15d428fcdf8b2f4833a10228a48ed82690e636275b08' 
  AND token = 'mGyLwdux+WBN3GgKlT+DN2po2DRDImS07kvMOUF23EI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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