SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84d3cabd5f91ee41baefa0f335a9b72bdc072cae0d9fe78618f39803b76f6f13' 
  AND token = 'D+4sehBO/IplplC+CGYJcRBjDbSeSPWjBH5EB4SfvwA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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