SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c936bbe6236e40e9ece0fefa2afedf0187cc218c84a383d1e8d1f3ac3bee4ee' 
  AND token = 'UY7UJwZT5YC8U0KQge6M+eH5EQ9Q/w1deYaA27f0ufw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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