SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9c2a7b136a0dc8400cd8df954bb7582f208a43d959404137c446c38fe19aa6da' 
  AND token = 'uGsA7wXYzkY2HenYZ0SyB6AraG9G/L/itG/P23KLmJo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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