SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b9edb8a1be6677a737cf7852fd6ee3ae7b244a061f11a1736cc80e47fa940a18' 
  AND token = 'ieqdQHRkRvNrd1S5wVmiFzDtZ7Jf418qMzYaYDbD158=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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