SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b4ed74c195169d48115e44e2bc67a2feb9aeecd185b46fb4bccf36f63adcc0a8' 
  AND token = 'L0CoBBZPYv1ucQ4OcnDsHHUL+sv+tjNQMVHGgNMM1tI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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