SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'db33c7ea14142dc6edee000b63d53b6ce7640a710c813ecc0a5deaa99613c7ee' 
  AND token = 'q8sPTZX78fzyaLH7t/TRZh/DGEajjv9w/dK/11EtDfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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