Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '15cd4a95034306255bef375504e714f318e2bbfa64406ea134db02e7050502ea' 
  AND token = '7c/6yj3xbJNMJ3uhFEs2ZuG/bgAGVeTXmBmVwzsMGnk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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