SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '987194c64699953b3066da4c34df79a002a87e90282f755900722ff4929b31d7' 
  AND token = 'KhriGjt85ILpX0VXkSD/8wAealuZH1sBnvK2+CQZpQ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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