SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'edbb5c8d0cc652001869cbd742d27523b8ed5c08a68b56d329cd0d8bb8e11856' 
  AND token = 'NvhuyP0JzhmIiNsgKK9PfmE7Ccp6VrqXmR8eA1qzXYk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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