SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd857807b35d33401793431d9b2fe30d8910e7aa538926742501d4479f54751e4' 
  AND token = 'p2qdugaM66YQQ3wXrIW+9WAsol4VZcxGzH0XyI1jLXQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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