SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b5c4177cdf00a329ab1a55f0e19a307617355cb4994bcf946e5a24d34fdcd7a' 
  AND token = 'qFwUPx6e+d9GygTGgfty0ldwuwbSalVjWmREAHHIQto=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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