SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2408bab8e61e778b0d858075fba41e134bbd5fb87b29f163fa237942f3cec620' 
  AND token = 'h7UvGWfo/YWQlg6yaoqUCNuqw4CpLAab2e/ZYM2Kajw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}