SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d3e3a68c67c49bfc6905965438faa36bfc705980c9922c141b617af8c748ccd' 
  AND token = 'VQFPdaNNY8iUpZiGlnNWC7kfbnjXMCAnjn9WIBc7NmE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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