SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '3be7d8eda5f8be2e5fdc20e2af14fa11374b6e076ad1427810862c87c13ebd7e' 
  AND token = '/Lp7nviEjW/lMM9qDvL4NryPUZloJyH40vP/beO9O8E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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