SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd70dbc52839b64e20398d8dfc4f01475bfe8adaa924d6ac4be37d6d32454cf32' 
  AND token = 'oy+W5DQXuaH+AUEKYfrMiagkUkwESZeMKhsNo4zsaPk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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