SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '899e6bd08f8bc1e337cb825c381643fa71bfeb886ad0acaeb41c93d4cf9603a3' 
  AND token = 'OzsMEWyEa5QdD4xdFk3t7xluaGK3zeWcY4LJ4oRcgR8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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