SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '5b58c06367c8963fd82f2d346fbbb621569871087a410f2b0bd908effb7ebc36' 
  AND token = 'IspqNN0h4j389UpuVOg3XhRbUeNWSXTikBTn4+Cpiis=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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