SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '82e93242ea69257213bf69ad48735d43db0bb41ebf8dc75319354ceccf70df03' 
  AND token = 'zf17oxmQHJxwpcwrTcENRb1aiOIEFCQ0tP2ZWD77OBk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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