SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3b1717ab8f3910ff6d1a67aafe94f8c90ca2929c278d131145a35be5eadae7d6' 
  AND token = 'Jgx18dPO0qvhGEF+qHO0zoH8PXBqPzwcnzF/voVP97A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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