SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '967b4df5fbad868ba7d249f76c1be5293ed769d74e4a4debb836774a5898fb3d' 
  AND token = '+MzC/VWHSyWlqI21VX2ffqi+4YQtLf8G+QJhyByK6H8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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