SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '2ec0558ca915fce9dbc6d747882a321e9d4d33ca6080b97521deb98259dff7a2' 
  AND token = 'JBeLemUWPAhj5P4BjRoUKpyKAr0ornIFdhbCLZjI9oE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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