SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '527efcd98a19639ec4db52655d483f43772c0aee8e32a70d66b11992c1dfb18f' 
  AND token = 'wQ1cCJInIUcU0yTfUUl5FZlxiPmml9bADUQ0XUAlSkI=' 
  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"
    }
  }
}