SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc3f169372dbdcac2a81bbe115883646f2392e0e7a9fcb67895299ef1324e606' 
  AND token = 'TMbxBjImxrfP2fDrDhvXk0ljo5zYXrLGghKw5vbRaOs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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