SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed8cc1172095987146d86f8820581e0de10001613fdcfca1c4a101d0247ead0c' 
  AND token = '10N9M/Zah97KxqM1VkFl2Z21DpYXNFX+5XxPMZp1+Ww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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