SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '92f9f6395a28064a73c3ec175aef240148a14cb521e4ef2f835202b1a69b10b9' 
  AND token = 'vH0QsIzoWAFsqd26aDJRUIcARSaj/33Du8eYf0RQjVE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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