SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '4b1a06ad63e7c5c7602393a4377f6112981c402bf9ff17ec9932bab33a3d5bcb' 
  AND token = 'DkqUvrCdWVjKOIDJ8GDP52Zkrvmp40tf7bN5slgt0TU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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