SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd980a3045f496f64f68e55b3160d8d8fc6815d3c8801a0424e85670033e7a7e2' 
  AND token = 'CZCanmMxb3d+JQK9kGnb5aKJDLjU+v634XPI2RnE/hQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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