SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6fc0b2367d83a18b415bcbc01293fa10a0fb50b5b63f7f657fff9520d7e6e7fa' 
  AND token = 'WyJhwq9N0Zz4BaP9XTlsgXcdoB8Dh5yYh4/9Y8hGCas=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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