SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '530128b1599a21cb2c76f28802c461aac991246060ed1fe464f0dea39b766364' 
  AND token = 'RzK+LBRYNYvslZ7koMEHCRFtKHGVQD6tZla9OuHZG4o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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