SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aab1aeeabc26e59649144d948ef8fd3eda4e5e8c1bcf5b0eed83177a72c80935' 
  AND token = 'XZSl0BwjfCH5oNEVzJzEmXPJnYYavcNQGLMz4Fl4rgM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00009

JSON explain

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