SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2cbd89170ac5532a734bfb66002bd30601fed466023fd2595e9ede066e4ea1a3' 
  AND token = '4iENr5LPUmbHLKTvB0+5n/tb4+bCO+M9kgS6qLYRrK0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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