SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '3c813141ecb1f925e08e46e4839a6f075e39b08b71f342809fe5a0f74e3d92cc' 
  AND token = 'LGWH8eC+K7QCwrKAo/dTKtyw/PrXlX1gDkuYccfskrg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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