Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd51d181f0db2a112fc71d0631dce0f5b0099fedbf402597626ce5438cfdf4b46' 
  AND token = 'oVhEXr/DXwbebTYQetjIOeWYzDSHpGfPHo6OvVpy9L8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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