SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0dc462f56af15f43525605c0957034da988c1b3ac259f2e0a613e6eb40818c63' 
  AND token = 'HSbJ/9fsNQbt4xHpjaPONpSVxwQIh3I9npDS7bzyE5I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

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