SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '415f844a06446a58df71aab2316e230fddc6d9fc6f166aecc9584bb957b19d97' 
  AND token = 'yB8s77MIx9/QOpKmquchPTrme9gcBBx1+XXyv5jzm9Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00229

JSON explain

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