SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e9e148c6b3807ca892251f3202e2277f3b3a056dd86f906afe37f44d2664fdb' 
  AND token = 'Gv4qxPzTovkXMGcbQgHYzH6DkAfIuZXwDBjdl5WbReA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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