SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '3b64b75106cf131fbafc690d512493ff63f1d080cc5e69c9a7ed1e9442eb8dfb' 
  AND token = 'habUEfumPrRavUIcv+wsXwAarC1v6RCZjJ2SOdW+Ve0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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