SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '30bb24e823d78f352061e091061e6782e70fda92d0d777db9490bdaa621fec3d' 
  AND token = 'ZjgVTRyyMLAQjcnBcm1tyqWD8BgiG2PUrV2LKBMvzNI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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