SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '2209b6d2bf909013015614beeb338ec95c8ad99797ee96571057ab40ebb93c22' 
  AND token = 'gHk0FbPHsZCvMYltUUJX+8vClz3SnKIdrXXXVHel2fg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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