SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '232172872ee87f5119350a88492e997e5c99e9091c66d27faa9e9856533b4f09' 
  AND token = '+kAA+8K2bo+hWHMlK3Y8RFUKpqIPSifgMKUdwWPScMw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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