SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '1bc0cb6352b9aff8086429436215a3f0ea49fe6eb4c8e3a41b775f0db124ceaa' 
  AND token = 'tWNgaz5V5d/wnWDQWOmlV2XXkoQG1PpYhYdPDdl1Wb4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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