SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '368fd34b046e8948d35a503456d65daf76d94d9c5d8f0695aadfd61281748e13' 
  AND token = 'j35RyQ9z6O/wWO5O+DzbqJxKGEZK16H9WS/2v/BGcfI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}