SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4da7e770e81b5e2081ba0c51c1dc7e42408029e93dd5372d163068e9ca1db749' 
  AND token = 'XP7zBjrIuAmuE4b9oQmnj61WxgWe2TDDjD5neMRND/g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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