SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '019bab2e5cc28abd37e85940ee9900a314ca87c60b98dd249057e4d080eff6eb' 
  AND token = 'LHfSGPRSNotWWqiINisERaJSGZ4YEg3IUjVOBLdfO1A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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