SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30f6ac4352e0fafb1b8821f06b586d978bbf6e76bc7d4e73362bdc8f645261e2' 
  AND token = 'BJJGZesqoaEpLhLMGCXRc5CYiFbNGSWM6mBVXF+Tj+A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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