Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b5866f4af1f32bf23a513f4aea2d9375e07d8568ee62e50a3325bbc9ee6a5ef9' 
  AND token = 'JeJXCqy0P/Q+DvV1YlVPyLyF8pHplsNlOYp0yEjwe8c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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