SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a0c13ee4ad6362c506ef073828aec9de82fd4869d70c88ac546abe82553257e' 
  AND token = 'j3AceUtNBmvKjy/oFLagihyZxE2ZpgeYYXvJroVg2NA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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