SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '87051669b03fe9e93d55fef7e702f9c449795b3dbb663af047a569f9b3af339a' 
  AND token = 'F4ohwyvDkt2QGkmP1InHExRt8YxfObAuPCNi+iYFT+0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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