SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5cff982a7b71bf29139ca5d80df15933ad91f3b6fd9f7af23e7c4977e63c04fd' 
  AND token = 'zhwqo5FBuCAfGFnOPp1620xFvl7mUFOXdkI8GWpgzh0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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