SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37061d5028b87055c9f7a5e591d6bb279a2aaf6b559f79b028abaa6b147557e6' 
  AND token = 'SHWUFDJHOJEU+OYSBuIv9PncAHKqGRAOJskdJGGh5tU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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