SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9899cb53457f6f85a56420b8bf5b55b9dd86a42960d1fb990e54dc29178bc77b' 
  AND token = 'QXQRtufq8yrgLeL/OzrhYOoyjdjL1TLsv+hCO6ZHwWQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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