SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ea4ca0e49a10a5bf369662cba119219dff84eff8ec01788cf6b7d7ff6f9884a' 
  AND token = '84KBbSllWNYiHbxmZBhSxkFjesVJ+FYvULYWezBLHF0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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