SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9a6f2d393251927820bd0196ff15eaf380a6beb179e9ae6eaec64970d5f90175' 
  AND token = 'zFZfUPAjU4/Rhwaf7mAPaG7hGHG4L9c/zoSB4yOPSY4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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