SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c8b6d5998ec3b8cb1eb29794a0b939142f8f135ada2041153875a386d9d66cc' 
  AND token = 'F48Eqn3zM4VtLuajhh7q2ZzG/4dhNsyuBgEZ+j33Xzg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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