SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a02324e502c6fa82e5844db2fc0f9b279758c81824ff90932c0676aba29a3234' 
  AND token = 't3NSPqH5z/bm+Ob5TiF+1h5VyPZ7gLWVwcv3xsKeMCQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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