SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63e2d4f1cd014e7ba72aa0e54912358575b2c7b78d222eecdc936bd91df72cc9' 
  AND token = 'T/q2pZSdlH0sUkTzxPQVM1LzVGwjERPBwKaEONHGx6A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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