SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f5707b91d73e90d8efcba83f335cfec5475940365f46196ab08121ed9ac556c' 
  AND token = 'GY8QlIwSb9CXM5Bdir3/wDt8kTaapJRsR9sjMO94JKE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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