SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30a52f108533e7a877ab1ca15cb8d326103a48cee2a314ef57433247b036a188' 
  AND token = 'fBfMyRuVfb6HEW3Ksb7neTFoq4vlMEeHwEG7gyMLXsE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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