SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3f25c7b0c0a3184c38d25d74c2272b927b9467d38245b48d9f0bd9210acb04c3' 
  AND token = '7TpFkAfbXYxm37KgV/UvS9yefNOrqLi/+beS6WmKPPc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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