SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0db94568befb5ab677d2383f0a2e92ed9e3ff2b23ca98b280d10c910ba14c3de' 
  AND token = 'oZYNYtdDSuWZee0i2jlwD3d24IDa29IVpRNGtluBbCE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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