SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95fd313286b8d1cadcb2632777501ac07f945f953358ee0fd74b2b5ae82e5782' 
  AND token = 'iDwae0UkdLe6MHxmXlubUSckDvGkRD7aX7uJndGjJXI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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