SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '60e4c277d952dec1a71b9bd09c0564311a40c8b8dc42803d63a471441316c15a' 
  AND token = 'oNFEOvhmMMqxTGr5th30glFvbzhy1LVbPQlzrk3XJBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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