SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47a5a247aa4b152f8470319b2349fb9f2d116048610166a722e95b37be9eb011' 
  AND token = 'mGKjgYCDT8Waa85StDRsYjfyBkmJAdyKLnPYt/QXJPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00083

JSON explain

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