SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30d8603e02c9050e157eef0ab4e566d791f3565b45c015138ee54bfd8ec10079' 
  AND token = 'AidbTgLBZFNW/Uix6pF7xaaG8rTVazWyRPJC+4ux39s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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