SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f12b7597521d6c884d642ce2a3de1c99c6a5cd029bd4a605ac876a26d0ea1b6b' 
  AND token = 'G1WPDvfO/l9YCqef1XBo3ng6JfMBZuiruG63nOh//Qo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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