SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c396031a42ada59cb7853581cfbd70bf0c3fc7bb1d6173d5da1f6b703264521e' 
  AND token = 'wkR/O7PSpc7JXB/9rI5UHRzPlePTmVuDfxNV8lz5dhY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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