SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d41ae8795adfe165824af9a81308270c193ec4cbd6313d2209e4398353e1385' 
  AND token = 'CZQFnUh5J7+67rhlYGYiANJTlZ8RNj5XwWSqHyRIaH0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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