SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b8211614babeaf4f1812a8f8f4ca076fba91dfe8f1de62f1f0e3a5549f11740b' 
  AND token = '94mvSrViQ4t5tOpIJdnV9xFVwYsB5VrAUtiosE2b4ao=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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