SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc887f6d6b9a457c2c334e9d1939f7fb0cad03137f5852ad5f349d8c02760531' 
  AND token = 'WC3ZsgnOKDGTSeWFtrej/eX8KbP14uY/VuDhQpMnxNU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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