SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da0b119f03f24e0a2c4204786ec05068bd32039267968f6faaa778a6c08d3b38' 
  AND token = '7T/+Z8Yh2JOEMrUXY3t/7zkyOU3u6PydVwHL4BqvL/s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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