SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93fb3b3b2ead558e6e26ac1558607cccd121b89d8591d84584653f70a44abd5d' 
  AND token = 'GXNZD8UwYKFrDmdOcuUQSSjssQJh0yOm0PnXZxedSss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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