SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '44c8455dcc0b649bc4538e6964f442bee282b84c343f9c6c724adc4c068f0f92' 
  AND token = 'gwbBfCv792pnzpY1dqqhhZ5h8MtJCnLJNgksV8ipNfw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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