SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77a127af1b54dd2a89b409f8c8cc31b96b09d6be781418dd1452d1e5ab262f4c' 
  AND token = 't71YVyjh4zlugvXZhv/WLrXtCp0cgcoc/TPDr+QBewA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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