SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '046483fc2f3c57168c7a7278ca13dd6f165ddbf498b9ab995958dbc0b6ba915a' 
  AND token = 'Wjq7I1SH9FHaWd2vfTdOwwZu/YBrHtqCpDLRyHqG7lo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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