SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46c516199ed8a15fb402c4ceab31922083fd17dff1e649dc1a5be34a831f1b53' 
  AND token = 'TH/UG7QA8EMNjC8Hxs9e9sm4B1Qsg8AIrTWVffMWYaQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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