SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f227b8188bd34765172d57a6404b8a94ef1e9084afa832bcc439ffb3f138d7df' 
  AND token = 'tmkCAlNpxi9tUYaG6/VrnqfbRkusr5ir2bSPUQXOuAQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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