SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '606240bf32671c6c0396f1d087439b5b171aa6da4a1c46d913b7bd6048b28d6f' 
  AND token = 'zGlOQN8f6iYaa82CAslE4TbH2dVkt3pUjHGuygKGeF8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00112

JSON explain

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