SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '4748300f30d5787c5a36770eacbe8ffe2bb1ecfe8d6f228fd8eb3af61139799f' 
  AND token = 'vRGa897TF1rX35wtpwpBhxQ1/inbulLYyoWDnWxi/8o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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