SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '129954673a71c83354c28c9a84393da533dac84b8f9fec703352305b3db943b0' 
  AND token = 'qe84+wjqKbkK938V331DwXmwZ0R6lSS1IxcG27SKe04=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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