SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c4565e834ff3751107110c1f38158c67bbf12191ab9483424269f79d895b0355' 
  AND token = 'AYd1fUA8IegADXkmv0DbktmZqqNiQxELX1LsvkSiIq8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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