SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '937f3e5aaa089c038e770486e607df55704a981c9a1e93f7d4340ed77215b5c0' 
  AND token = 'tt/bvO2IOLT9KPYWoo9hHzjlHUYPSNfQoIymyhAdhCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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