SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93acd18aefc12fd79eff3935cb54cb01384c70b8fb15d6ccfdca7413d9ff7148' 
  AND token = 'YaBFNq8wN/xPUPJMIv3c0B8o3gL9WKzZB7sNlZpmUnM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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