SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'e8cbe3a8084258c57797648799d6e98daa0fbd9950fffd2e673670c936e0203c' 
  AND token = 'qYgEWr1RzifSRCwsmpJ7vHKS07AgMxsYhyndVLxSxzY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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