SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '92992ed6e76baf7137c8e63c017fdc2ef74039e7c378b7ca57406657cbeca3e7' 
  AND token = 'y6GSFEAO4fJT5dAAdL1tzOCLwufTN787zIiq74yzSHY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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