SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b8b24735677d625ead507792d31561bfac702286b6ce2c44fd9ea230e11d062a' 
  AND token = '6J4ltDQklWgTAwsjYG9al8VhKIHPq/sr+2isLwQr+W0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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