SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '3f2c32ffc9f92d732ef344d7a3ddeb675959fbd65793d8c687c20564d528590f' 
  AND token = '1/y8NPpVzQVLHr6Tvt5b/z+/ia6dAJcy6ajv6nmoCVI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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