SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ba7ed809b2f12e31c20938348b7556c6e5cccb9bc6b8a21c43c7fa6def39879' 
  AND token = '8Ih/78wDm064xsBjc8N1c5wAdLMQjJbGc/tZLCaMKQI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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