SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9d9439eb5dd1dfd904c935b782697bbfc9ebc213a11dd2ab560575c06728e26' 
  AND token = 'zG+dj6GvVVHgQJGlJuHnZHh/NYDhxImkyow+Vcn/alk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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