SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7565d3068a8c2cdaa647749a1e838479a339a7b1812c7edf7b39e61e292a0f52' 
  AND token = 'gysAvB7oqnVSfazx5Ah4VGwmbvyvuO47Y+oMan+OOy8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}