SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5fdd11a20f33fd5926de9bc7f792848dfeace034070932110ad2658211f8c0b5' 
  AND token = 'bWCiPrfU6OLsmNTnwGpkBCmdyzFBuiA32vb+pmrCbyc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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