SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01ec19eeff9ef09f47ffc7a66ba77a67a16eb3d02be6ac302693af786dd2eb55' 
  AND token = 'pIVsC3pAMcYzNQSL4hz4+m72WehSYLrLLXQsutnhk0c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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