SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13a5e1ac573a3fd2fd62dbd3cd1694f848473b662b27d657261c43387203337d' 
  AND token = 'WUGsJO0BQZdqnvJSrkgLx7D2ye8QlhypIFwwVUEs14M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00071

JSON explain

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