SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0f078b03bc7835b12e26163dc3e61f231c8f9da0ede131a6de0027b3dea4e665' 
  AND token = 'df/FOsoyi91U565l3wAmUCi2DAl7SWOkNApd6AyVyDI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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