SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48ff4e493601c24c73b6a22795249440573f516d26cf8e3b24c5cc2d26e1c650' 
  AND token = 'd9c7apNQMqsaBpIJX48RGPmXBFBwQVYXKJXRYZQKdsI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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