SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf4d5de640b2fd032f428fadab20c674f663d0865c14166fd172a26d61aad969' 
  AND token = '15KUo9Z8RUMhu3afUBOeQj6tE9uFP72E+Y9xZ/K91ks=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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