SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ff7af27e603a7d26e5d4fbd361c5c5bf85ecb7b3d2324e969909683bde25830' 
  AND token = 'vdraNf03m+MDFlrCwwv/97isY29SeCybThqe7Gi1bZg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}