SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '019b1f3b4673e4c7869beb68d21ee0808b7fa6640e8ef7e2596e1742add0a7fc' 
  AND token = '4UXwd7+GkS0gtMk3O9xhTZDaiCHAbp0TI/VizqiY9+c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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